It is well known that composite parts reduce in thickness during cure. This process is known as “debulking” and is almost entirely due to the release of entrapped air. Typically the reduction in thickness of a pre-impregnated laminate (commonly known as a “prepreg”) is of the order of 10-15%, and for a dry fabric composite the reduction can be even greater. This can become a significant problem when either:                a) the part is of a significant thickness (typically >10 mm) and is at least partly non-planar; or        b) the part incorporates padup areas a lot thicker than that of the surrounding material.        
A method of hot debulking a composite part prior to cure is described in WO 2008/007140. The part is formed and debulked on a male tool. A problem with this arrangement is that only a single composite part orientation can be manufactured at a time. Therefore if multiple parts are to be hot debulked simultaneously using such standard apparatus they must be positioned tip to tail in the same orientation which will require a long and heavy male tool.